Navigation systems provide end users with various navigation-related functions and features. For example, some navigation systems are able to determine an optimum route to travel along a road network from an origin location to a destination location in a geographic region. Using input from the end user, the navigation system examines potential routes between the origin location and the destination location to determine the optimum route. The navigation system may then provide the end user with information about the optimum route in the form of guidance that identifies the maneuvers required to be taken by the end user to travel from the origin to the destination location. Some navigation systems are able to show detailed maps on displays outlining the route, the types of maneuvers to be taken at various locations along the route, locations of certain types of features, and so on.
In order to provide these and other navigation-related functions and features, navigation systems use geographic data. The geographic data may be in the form of one or more geographic databases that include data representing physical features in the geographic region. The represented geographic features may include one-way streets, position of the roads, speed limits along portions of roads, address ranges along the road portions, turn restrictions at intersections of roads, direction restrictions, such as one-way streets, and so on. Additionally, the geographic data may include points of interests, such as businesses, facilities, restaurants, hotels, airports, gas stations, stadiums, police stations, and so on.
Although navigation systems provide many important features, there continues to be room for new features and improvements. One area in which there is room for improvement relates to providing guidance to follow a route. The geographic data used in conventional navigation systems is static. The geographic data is stored ahead of time in the database representing physical features that do not generally change over time. The optimal landmarks or features in the geographic region to provide the navigation-related functions and features may not be included in the conventional geographic database.